Inflatables have found use in industry in a wide variety of functions. In some such functions, such as in aircraft escape slides, it is necessary that the inflatable be resistant to substantial quantities of radiant heat for a time period sufficient for the inflatable to perform its intended function. For inflatable evacuation slides such as may be employed in evacuating an aircraft or other escape structure, the time period for which predetermined quantities of radiant heat must be tolerated by the air slide are typically by administrative regulation such as is set forth in Federal Aviation Administration (FAA) regulations and standards, and particularly in FAA/TSO-69A Appendix II. Exposure to intense radient heat can cause deflation as a result of the premature formation of holes.
Traditionally, inflatables are formed of one or more plies of fabric defining an inflatable chamber. An inner surface of the plies of fabric typically is formed of a substance having the properties of retaining air within the inflatable such as a urethane coating or Neoprene.RTM. rubber coating. An outer surface of the inflatable structure typically is coated with an aluminum rich substance, at least where radiant heat resistance is mandated. The resulting aluminum rich coating functions to reflect away a substantial portion of radiant heat impinging upon the inflatable structure and thereby provides protection against the radiant heat. In zones of high wear or great stress, a plurality of fabric plies typically can be employed. Again, the innermost ply includes an inner air retaining urethane layer and the outer surface of the multitude of plies is coated with an aluminum rich substance for radiant heat protection.
Inflatable structures often are employed for emergency evacuation purposes such as in forming evacuation slides for aircraft. It is important in such uses that instructions on such slides be highly visible and easily located as, frequently, these instructions must be read and understood in times of great duress. The point at which such instructions are required varies from inflatable structure to inflatable structure and is in part a function of the use to which the structure is put.
Whether these instructions have been placed on a signage substrate fastened or adhered to the inflatable structure in some manner, or whether these instructions have been stenciled directly onto the inflatable, the application of instructions traditionally has negatively influenced the radiant heat resistance of the inflatable structure. Fastening members employed to fasten a substrate bearing the instructions to the inflatable member have functioned to conduct heat to the inflatable causing premature leakage. The substrates themselves can cause heating of the air inflatable due to the absorption of radiant heat by the substrate and subsequent transfer to the inflatable member and lead to premature inflatable failure.
In past suggestions, the substrate bearing a legend was fixed to the air inflatable and formed from a reflective substance such as aluminum foil. Such reflective substrates can be difficult to adhere to an inflatable and can become damaged during folding of an inflatable for storage.
In past suggestions, where stenciling was applied directly to the inflatable, the ink with which such direct stenciling has been accomplished upon an inflatable has included a substantial proportion of aluminum thereby producing a paint conubfigured to reflect a great amount of radiant heat and slow the process by which radiant heat produces holes and thereby an air loss in the air inflatable. Such aluminum containing paints have proved difficult to view under many lighting conditions and have been less highly visible than would be desired particularly in flickening light such as may result from a fire.
Accordingly, a means for direct stenciling on an inflatable employing highly visible colors while still permitting a radiant heat rejection sufficient to qualify the inflatables for uses such as in escape slides for aircraft could find substantial commercial utility.